Lubrication by meltwater may have enabled massive slide
Although the world’s ice and snow is melting rapidly on a geologic time scale, it still seems to be a gradual process, at least for casual observers. But last summer, July 16, to be exact, 70 million tons of ice broke off the Aru Glacier in western Tibet and crashed far down into the valley, killing nine nomadic yak herders. NASA scientists reported on the avalanche here.
A team of scientists who analyzed the giant avalanche now say there’s a good chance that global warming was a key factor in the unusual slide. The researchers, who published their findings this week in the Journal of Glaciology, said that that the avalanche lasted about four or five minutes, burying 3.7 square miles of the valley floor in that time. Something — likely meltwater at the base of the glacier — must have lubricated the ice to speed its flow down the mountain, they said. Continue reading “Study eyes link between giant Tibet avalanche and global warming”→
U.S. Geological Survey scientists have completed one of the first experimental studies to explore links between climate change and invasive species, specifically how brook trout and brown trout interact with rising stream temperatures. They found that non-native browns limit the ability of brook trout to use warmer water temperatures, By contrast, removin of browns brook trouts’ reach into warmer waters.
Links to our climate and international news reporting …
By Bob Berwyn
Not as much content as usual on Summit Voice this week, but that’s because we were busy reporting elsewhere, with a few noteworthy stories. For example, Austria is holding a presidential election tomorrow (Sunday, Dec. 4) and the election of Donald Trump became an issue in the last few weeks of the campaign. I co-reported a story on the election with the European bureau chief of the Christian Science Monitor, including an interview with an American expat involved in the campaign.
Scientists eye winter ecosystems in ice-covered lakes
A team of international scientists who studied more than 100 lakes during the winter said there’s more going on beneath the ice than we realized. Their findings stand to complicate the understanding of freshwater systems just as climate change is warming lakes around the planet, and shortening the ice season on many lakes. Other parts of the planet’s cryosphere are also melting under the thickening layer of heat-trapping greenhouse gas pollution.
“As ice seasons are getting shorter around the world, we are losing ice without a deep understanding of what we are losing,” said Stephanie Hampton, a Washington State University professor and lead author of a new study published in the journal Ecology Letters. “Food for fish, the chemical processes that affect their oxygen and greenhouse gas emissions will shift as ice recedes.” Continue reading “Life under the ice”→
Oil washed toward shore after the 2010 Deepwater Horizon disaster is a big factor in coastal erosion rates, according to scientists with NASA and the U.S. Geologicial Survey who tracked the changes along the Gulf of Mexico. Their research shows a pattern of dramatic, widespread shoreline loss” along the Louisiana’s coast in Barataria Bay, located on the western side of the Mississippi River Delta.
There could be more trouble ahead for pollinators, as a new species of Varroa mite is developing the ability to parasitize European honeybees. That’s a new threat for insects already under pressure from pesticides, nutritional deficiencies and disease, according to a Purdue University study.
The scienists found some populations of Varroa jacobsoni mites are shifting from feeding and reproducing on Asian honeybees, their preferred host, to European honeybees, the primary species used for crop pollination and honey production worldwide. To bee researchers, it’s a grimly familiar story: V. destructor made the same host leap at least 60 years ago, spreading rapidly to become the most important global health threat to European honeybees. Continue reading “Study IDs new parasite threat to honeybees”→